CVE-2021-45955: Thekelleys Dnsmasq

Critical severity, CVSS 9.8. EPSS: 2.5% chance of exploitation in the next 30 days.

Dnsmasq 2.86 has a heap-based buffer overflow in resize_packet (called from FuzzResizePacket and fuzz_rfc1035.c) because of the lack of a proper bounds check upon pseudo header re-insertion. NOTE: the vendor's position is that CVE-2021-45951 through CVE-2021-45957 "do not represent real vulnerabilities, to the best of our knowledge." However, a contributor states that a security patch (mentioned in 016162.html) is needed

Affected products

• Thekelleys Dnsmasq: version 2.86 only

Published 2022-01-01. Last modified 2026-06-17.